Anatolius was bishop of Constantinople (449–458 CE) during the Council of Chalcedon (451 CE; ) and one of the key figures responsible for drafting the Chalcedonian Definition. His role in the events surrounding the council (Councils/Synods) brought him into conflict with Leo the Great of Rome (Leo I [Bishop of Rome), particularly concerning the controversial canon 28, which gave the see of Constantinople preeminence after Rome, and Leo’s frequently hostile letters are a crucial source for reconstructing Anatolius’ career. His early life is unknown, although …